x86 tsc: mark %eax as earlyclobber in tscp_get_timecount_low().
i386 codegen insists on preloading tc_priv into register on i386, and this register cannot be %eax because RDTSCP instruction clobbers it before it is used. Reported and tested by: dim MFC after: 6 days Sponsored by: The FreeBSD Foundation
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@ -826,7 +826,7 @@ tscp_get_timecount_low(struct timecounter *tc)
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uint32_t rv;
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__asm __volatile("rdtscp; movl %1, %%ecx; shrd %%cl, %%edx, %0"
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: "=a" (rv) : "m" (tc->tc_priv) : "ecx", "edx");
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: "=&a" (rv) : "m" (tc->tc_priv) : "ecx", "edx");
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return (rv);
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}
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